"...came up with pretty much the same calibration values."

HUH?

The actual amount of any offset required when calibrating (or, more correctly, adjusting the unit to the variables of the processor, amp, speakers and room) a processor or receiver may or may not be the same. That they are or aren't is of no value since it is not something you compare. The goal, as I presume you know, is to set the output levels so that all channels are equal. How you get there is of little consequence and ascribes no goodness to one unit or another.